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Antioxidant And Cytotoxic Properties Of Salvia Absconditiflora And Effects On Cyp1a1, Cyp1b1 Gene Expressions In Breast Cancer Cell LinesYilmaz, Selis 01 January 2013 (has links) (PDF)
Salvia genus is a widely cultivated genus and used in medicine for various purposes as having antimicrobial, antioxidant, anticarcinogen and anti-inflammatory features. In this study the aim was to investigate phenolic composition of Salvia absconditiflora and understand the possible effects of those constituents in cancer related drug metabolizing enzymes. Salvia absconditiflora showed 80,43 % Radical Scavenging Activity against DPPH radical. Total flavonoid content was found as one third of total phenolic content. Presence of important phenolic acids and flavonoids such as caffeic acid, luteolin, coumaric acid are validated with LC-MS/MS analysis.
Cytotoxicity of Salvia absconditiflora treatment on MCF-7 and MDA-MB-231 breast cancer cell lines were investigated through XTT and TBE assays both dose and time dependent manner. Cell proliferation was inhibited 50 % by different IC50 values calculated in different assays and different time intervals. This suggests that two breast cancer cell lines response in a different way to cytotoxic treatments. Cancer related drug metabolizing enzyme gene modulations were investigated with qRT-PCR. CYP1A1 and CYP1B1 were upregulated in MCF-7 but down-regulated in MDA-MB-231 cells in response to Salvia absconditiflora treatment.
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Antioxidant And Cytotoxic Properties Of Salvia Absconditiflora And Effects On Cyp1a1, Cyp1b1 Gene Expressions In Breast Cancer Cell LinesYilmaz, Selis 01 January 2013 (has links) (PDF)
Salvia genus is a widely cultivated genus and used in medicine for various purposes as having
antimicrobial, antioxidant, anticarcinogen and anti-inflammatory features. In this study the aim
was to investigate phenolic composition of Salvia absconditiflora and understand the possible
effects of those constituents in cancer related drug metabolizing enzymes. Salvia absconditiflora
showed 80,43 % Radical Scavenging Activity against DPPH radical. Total flavonoid content was
found as one third of total phenolic content. Presence of important phenolic acids and flavonoids
such as caffeic acid, luteolin, coumaric acid are validated with LC-MS/MS analysis. Cytotoxicity of
Salvia absconditiflora treatment on MCF-7 and MDA-MB-231 breast cancer cell lines were
investigated through XTT and TBE assays both dose and time dependent manner. Cell
proliferation was inhibited 50 % by different IC50 values calculated in different assays and different
time intervals. This suggests that two breast cancer cell lines response in a different way to
cytotoxic treatments. Cancer related drug metabolizing enzyme gene modulations were
investigated with qRT-PCR. CYP1A1 and CYP1B1 were up-regulated in MCF-7 but down-regulated
in MDA-MB-231 cells in response to Salvia absconditiflora treatment.
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Cell Targeted Ribosome Inactivating Proteins Derived from Protein Combinatorial LibrariesPerampalam, Subodini 01 August 2008 (has links)
Combinatorial protein libraries based on a protein template offer a vast potential for deriving protein variants harboring new receptor specificity while retaining other tem-plate functions to serve as library search-engines, cell-routing sequences and therapeutic domains. This concept was tested with the design and synthesis of protein libraries where short random peptide motifs were embedded directly within the catalytic A subunit of the bacterial ribosome-inactivating protein (RIP) known as Shiga-like toxin 1 (SLT-1). More precisely, a seven amino acid peptide epitope (PDTRPAP) was inserted between residues 245-246 of its A subunit (SLT-1APDTRPAP) and shown to preserve catalytic function while exposing the epitope. SLT-1 A chain libraries harboring tripep-tide and heptapeptide random elements were subsequently constructed, screened and shown to express more than 90% of expected cytotoxic A chain variants. Finally, more than 9,000 purified SLT-1 A chain variants were screened using their ribosome-inactivating function in a cell-based assay to identify mutants that are able to kill human melanoma 518-A2 cells. This search led to the striking discovery of a single chain RIP that displays selectivity for a panel of human melanoma cell lines as well as minimal immunogenicity when injected repeatedly into mice. This directed evolution of a RIP template provides a broad platform for identifying cell type specific cytotoxic agents.
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Investigating the Relationship Between Structure, Ice Recrystallization Inhibition Activity and Cryopreservation Ability of Various Galactopyranose DerivativesTokarew, Jacqueline 31 May 2011 (has links)
The goal of our research is to generate cryopreservation agents derived from antifreeze
glycoproteins. One postulated mechanism of cell cryo-injury is ice recrystallization. It is known that simple saccharides and cryopreservation agents (DMSO) display ice recrystallization inhibition (IRI). This study assessed the cytotoxicity and cryopreservation ability of these sugars in relation to their IRI. It was determined that compounds with greater IRI have increased cytotoxicity yet confer cryoprotection. To further investigate how structure is affecting IRI activity, several galactopyranoside derivatives were synthesized. A series of deoxy and α-Callyl-
deoxy galactopyranoses were prepared. Testing determined that removal of any hydroxyl
group removes IRI. 3-deoxy-β-thiophenyl galactose was also synthesized and had surprisingly better IRI than β-thiophenylgalactose. Also, 6-azido galactose had similar IRI to 6-deoxy galactose. Lastly, a series of β- thioalkylgalactosides was synthesized and testing gave contradicting results which suggest that predicting IRI based on hydrophilicity is more complicated than initially hypothesized.
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Disease mechanisms in the C3H/HeJ Mouse Model of AlopeciaBarekatain, Armin 05 1900 (has links)
Alopecia areata (AA) is a chronic inflammatory disease of hair follicles manifesting as
patchy areas of hair loss on the scalp and body. Development of AA is associated with
pen- and intra-follicular inflammation of anagen stage hair follicles, primarily by CD4+
and CD8+ cells. We hypothesized that if cell-mediated cytotoxicy against hair follicles is
to be a component of the hair loss disease mechanism, increased expression of genes and
products typical of cytotoxic cells, as well as increased apoptosis activity within affected
hair follicles, would be expected to occur in the lesional skin compared to the normal
skin. Furthermore, we studied gene expression levels of multiple cytokines and
characteristic chemokines, using the C3FI/HeJ mouse model of AA. mRNA expression
levels of granzyme A, granzyme B, perform Fas, Fas ligand, TNF-cL, TNF-aRl and R2,
TRAIL, TRAILR, TRAMP, Thi-, Th2-, and Th17-associated cytokines, as well as
multiple chemokines were compared between the skin, draining lymph nodes, thymus
and spleens of normal and AA-affected mice using quantitative reverse transcriptase
PCR. FasL, granzyme A, granzyme B, pro- and anti-inflammatory cytokines were all
highly up-regulated in the skin of AA-affected mice. Immunohistochemical studies of the
skin revealed that, although greater numbers of granzyme B and FasL expressing cells
were present in AA affected skin, the cells were morphologically diffusely distributed
and not exclusively located within the focal pen- and intrafollicular infiltrate. The
majority of these cells were further characterized as mast cells, which were also found in
substantially greater numbers in the skin of mice with AA compared to their normal
haired controls. Almost no perform expressing cells were identified in AA affected
mouse skin and TUNEL staining suggested relatively limited apoptosis activity in hair
follicle keratinocytes. In conclusion, while granzymes and FasL may play important roles
in disease development, the profiles and patterns of expression are not consistent with
direct cell-mediated cytotoxic action against the follicular epithelium in chronic mouse
AA. Potentially, hair growth inhibiting cytokines may play a more dominant role in AA
development than previously thought. Furthermore, mast cells, with their increased
presence around hair follicles in the AA affected mouse skin and their ability to express
granzyme B and FasL, are suggested as potential key players in the pathogenesis of AA.
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Development of Organ-Specific Progenitor Cell Cultures as Efficacy Test Platforms for Electron-Spun Fibre Meshes in Regenerative Medicine ApplicationsRajendran, Vijayalakshmi January 2011 (has links)
The nervous and cardiovascular system plays the most complex and vital role in all organisms. Any damage or injury to these essential organs in our body results in long term irreversible impairment or death. The main goal of the regenerative medicine is to repair or recreate tissues using stem cells to restore the vital function of the targeted organ. Along with organ specific stem/progenitor cells, non-toxic, biodegradable synthetic polymers are also needed for an effective reparative therapy. The effect of PCL materials and surface modified (PEDOT coated) PCL materials of different topology with neural progenitor cells as test platforms are evaluated for cytotoxicity and neuron differentiation. The stem cells from heart are isolated and characterized as cardiac stem cells by Fluorescence activated cell sorting through specific antigen expression. The cardiac stem cells are used to establish effective proliferation and differentiation system. Hence, developing cardiac and neural progenitor cell cultures as an efficacy test platforms for biomaterials of different diameter and orientation benefits respective tissue engineering with proper restoration of function. Further, the nerve and cardiac tissue rejuvenation would serve as a regenerative therapy for numerous neurodegenerative disorders and cardiovascular disorders like myocardial infarction respectively.
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A Study of the Process and Causes of Abeta(25-35) Amyloid FormationRidinger, Katherine V. 2009 December 1900 (has links)
Amyloid fibrils results from a type of ordered polypeptide aggregation that is associated
with ailments such as Alzheimer's disease (AD). Annually, millions of people in the
United States alone develop and die from AD. Therefore, it is necessary to understand
not only the process of amyloid formation, but also the causes of this specific type of
aggregation. This study used ABeta(25-35) since it is a fragment of the Alzheimer?s
peptide that behaves like the full length peptide found in patients with AD.
To study the process of amyloid formation, several methods were used so that a more
complete picture of the stepped aggregation process could be realized. Several
oligomeric species were detected and described many of which could not have been
observed without using the complete battery of methods utilized here. The oligomeric
species detected included a novel 'rolled sheet' that appeared to be the immediate
precursor of amyloid fibrils, and two supermolecular species that appear after amyloid
fibrils were formed. In determining the causes of amyloid formation, two significant discoveries were made.
First, by partial sequence randomization, truncation, and Ala scanning mutagenesis, the
critical amyloidogenic region of ABeta(25-35) was found to be residues 30-35. This critical
core region is important because it is thought to be the region that initiates amyloid
formation, therefore knowing the residues involved in the region is a useful tool for
developing methods of fibril formation prevention. Second, by inserting all naturally
occurring amino acids into position 34 of ABeta(25-35), three distinct classes of variants
were observed and the effect of several physiochemical properties on amyloidosis were
examined. Hydrophobicity, solubility, and ?-strand propensity were found to affect
aggregation to the greatest extent. Also within these two studies, our results suggest that
early oligomers are the cytotoxic species as opposed to amyloid fibrils or other larger
macromolecular assemblies.
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Hplc-dad Isolation Of Antioxidant Compounds In Aesculus Hippocastanum Bark Extracts And Cytotoxic Effects On Hl-60 CellsOzdogan, Nizamettin 01 September 2007 (has links) (PDF)
This study was designed to investigate the cytotoxic and antioxidative properties of Aesculus hippocastanum L. (A. hippocastanum) bark extracts. Dried and powdered barks were extracted in ethanol, methanol, water and ethylacetate at a ratio of 1:6 (w/v). Antioxidative capacity of each extract (ethanol, methanol, water and ethylacetate) were determined by their ability to scavenge 1, 1 -diphenyl-2-picryl-hydrazyl radical (DPPH). Effective concentration (EC50) values were calculated as 0.010 mg/mL 0.011 mg/mL, 0.009 and 0.019 mg/mL, respectively for ethanol, methanol, ethylacetate and aqueous extracts. The highest DPPH radical scavenging activity was demonstrated by ethyl acetate among the four bark extracts of A. hippocastanum. Nevertheless, methanol extract was preferred for the separation, identification and further quantification of its phenolic compounds using HPLC method. Analytical and semi&ndash / preparative HPLC methods were applied to qualify and quantify the isolates. Human Myeloid Leukemia (HL - 60) cell line was used as a model system for the proliferation studies. HL - 60 cells were cultured in the presence of various concentrations (0 to 100 µ / g/mL) of methanol bark extract and, also, with the various concentrations of standard esculetin. HL-60 cell viability was examined by tryphan blue and the metabolism of tetrazolium salt XTT (2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) -carbonyl]-2H-tetrazolium hydroxide). XTT effective dose (ED50) values for the proliferation studies of methanol extract and standard esculetin were calculated as 56.18 µ / g/mL and 21.23 µ / g/mL, respectively. These results suggested that A. hippocastanum methanol bark extract and esculetin could be considered as a potent antioxidant and cytotoxic agent.
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Comparative Effects Of Emodin On Biological Activities Of Mcf-7 And Mda-231 Cell LinesSakalli, Elif 01 December 2010 (has links) (PDF)
Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a phytoestrogenic component of Rheum plant extracts which has been used for medical treatment since ancient times. It has been shown to have anti-inflammatory and anti-cancer effects. In our research, we aimed to study the biological effects of emodin on MCF-7 and MDA-231 cell lines.
Cytotoxicity assays showed that emodin treatment for 48hours caused a concentration dependent decrease in viable cell numbers of both cell lines. As determined by cell counting with tryphan blue, IC50 values were 8.40 and 12.17 µ / g/ml for MCF-7 and MDA-231 cells, respectively.
Apoptotic effects of emodin was investigated by measuring the changes in apoptotic and antiapoptotic gene expressions by qRT-PCR. In MCF-7 cells, Bax expression increased with increasing emodin concentrations, while Bcl-2 expression was downregulated. Bax/Bcl-2 ratio was calculated as 9.2 fold at 10µ / g emodin/ml treatment for 48 hours, indicating stimulation of apoptosis. However, Bax/Bcl-2 ratio was found 1.6 fold for MDA-231 cells. These results were in accordance with the results obtained from microarray analysis of related gene expressions. MCF-7 cells were more apoptotic in comparison to MDA-231 cells. DNA fragmentation was observed in MCF-7 cells by TUNEL method.
GST enzyme activity that was measured using CDNB as substrate, was increased 100% with respect to control up to 5µ / g emodin/ml treatment of MCF-7 cells for 48 hours. However, effect of emodin on GST activity in MDA-231 cells was found insignificant. According to microarray analysis results, emodin affected the gene expressions of GST isozymes in MCF-7 cells much more than in MDA-231 cells.
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Lipid peroxide and transition metals are required for the toxicity of oxidized low density lipoprotein to cultured endothelial cellsKuzuya, Fumio, Asai, Kanichi, Hayashi, Toshio, Funaki, Chiaki, Naito, Michitaka, Kuzuya, Masafumi 02 1900 (has links)
名古屋大学博士学位論文 学位の種類 : 博士(医学)(課程) 学位授与年月日:平成3年3月8日 葛谷雅文氏の博士論文として提出された
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